Constraints¶
PostgreSQL Global Development Group. (2026). Constraints. PostgreSQL 17 Documentation.
Cited by¶
2 citations across 2 artifacts.
Each citation links to the sentence it supports in the citing article.
Mechanisms¶
- Database Constraint
- Its strength is that it closes the gap between "the application is supposed to check this" and "this genuinely cannot happen": the invariant survives every code path, every bug, and every manual query, delivering true referential integrity as part of the database's consistency guarantee.
This sourceExplains that database constraints reject violating stored values and that foreign keys maintain referential integrity between related tables.
- Its strength is that it closes the gap between "the application is supposed to check this" and "this genuinely cannot happen": the invariant survives every code path, every bug, and every manual query, delivering true referential integrity as part of the database's consistency guarantee.
- Referential Integrity Constraint
- Its strength is a guarantee that is nearly free once declared: with the constraint in place, an entire class of corruption — orphaned records, broken joins, dangling pointers — becomes structurally impossible, enforced by the data layer regardless of which application writes.
This sourcePostgreSQL foreign keys enforce referential integrity at the database layer by rejecting unmatched non-null references and controlling changes to referenced rows.
- Its strength is a guarantee that is nearly free once declared: with the constraint in place, an entire class of corruption — orphaned records, broken joins, dangling pointers — becomes structurally impossible, enforced by the data layer regardless of which application writes.
Verification¶
Does it exist? Not checked yet. This entry carries no identifier to resolve. It was extracted from the citation as written in the article, normalized, and deduplicated against the rest of the registry.
Does it back the claim? Not recorded. Neither this nor any other of the 2 citations of this work carries a recorded support check.
Support is checked per citation rather than per work — the same source can be cited soundly in one article and wrongly in another. Per-citation recording began recently, so a citation with no recorded check is a gap in the record rather than evidence it went unchecked.
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Links previously used in the corpus¶
Before the registry existed this work was also linked 1 other way.
Registry ID ref:89767e30c96b · see in the full table